Dresden’s LTE/LTE+ like testbed was set up in 2008 as part of the Easy-C project (www.easy-c.com).

The signal processing hardware includes:

• Sorbas602 eNodeB Simulators with ZF Interface to a Sorbas Radio Unit ("ZF Interconnect”)
• Sorbas202 Test UEs  with ZF Interface to a Sorbas Radio Unit ("ZF Interconnect”)
• Sorbas472 Radio Units, by Signalion: EUTRAN band VII (2.5 - 2.57 GHz and 2.62 - 2.69 GHz) as well as close to band I (1.98-2 GHz and 2.17-2.19 GHz), 20MHz bandwidth, Tx power approx. 15dBm (indoor) and approx. 30dBm (outdoor), supports up to two Tx and two Rx channels.

They were supplied by Signalion (www.signalion.com). The eNBs and UEs are connected through IF interconnects at 70MHz with the radio unit frontend. The hardware supports up to two Tx and two Rx channels for MIMO capability. The testbed operates in EUTRAN band VII (DL @ 2670-2690 MHz / UL @ 2550-2570 MHz) with fixed bandwidth of 20MHz and in FDD mode.

The LTE testbed at TUD has been upgraded with a new spectrum license in the 2.1 GHz band (1980 MHz to 2000 MHz and 2170 MHz to 2190 MHz). This step was necessary to ensure the continuous operation of the LTE testbed when the spectrum license for 2.6 GHz is withdrawn due to commercial use of the corresponding frequencies in Germany. Along with the license, several nodes have been equipped with 2.1 GHz frontends. Note that only the RF parts have been replaced, while LTE eNB and UE baseband processing remains unaffected due to the modular structure of the equipment. Further note that as long as the 2.6 GHz license is not withdrawn, those frequencies are still available for experimentation.

The operation of the new equipment has been successfully tested. The internal US5 experiment “LTE Multi-Antenna Sensing” has been conducted in the 2.1 GHz frequency range.

Base station (eNB) and mobile terminal (UE) nodes each are connected to a host PC and configured with text files in XML format. The host computer also manages measurements of the received signals and stores them in dumps. At the eNBs, a GPS unit is used for synchronization, while the UEs employ GPS for position tracking. Additionally, UEs can be powered by a mobile power supply if necessary. 

Configuration of a baste station node (eNB)

Configuration of a mobile terminal node (UE)

All UEs in the testbed, as well as the indoor eNBs are equipped with Kathrein 800 10431 omnidirectional antennas. The antennas of the outdoor eNBs are sectorized and of type Kathrein 800 10551. You can find detailed information about these antennas here:

http://www.kathrein-scala.com/catalog/80010431.pdf
http://www.kathrein.de/en/mcs/catalogues/download/99811214.pdf

Other testbed equipment includes six batteries that can power an individual UE for around 2-4 hours, GPS receivers for time synchronization, various cables, attenuators and splitters. Measurement equipment includes spectrum analyzers Rohde & Schwarz FSH4, Rohde & Schwarz FSQ8 and Rohde & Schwarz TSMW. For more details click on following links:

R&S FSH4 data sheet:

http://www.test-italy.com/occasioni/2013/rs_fsh8-18/FSH_dat-sw_en.pdf

R&S FSQ8 data sheet:

http://cdn.rohde-schwarz.com/dl_downloads/dl_common_library/dl_brochures_and_datasheets/pdf_1/FSQ_dat-sw_en.pdf

R&S TSMW operating manual:

http://www.rohde-schwarz.de/file_9446/TSMW_Operating_Manual.pdf

R&S TSMW software manual: 

http://www.rohde-schwarz.de/file_11255/TSMW_Interface_and_Programming_Manual.pdf